Joseph m



NITED STATES PATENT OFFICE.

JOSEPH M. LIPPINCOTT, OF PITTSBURGH, PENNSYLVANIA.

LOCK.

Specification of Letters Patent No. 15,489., dated August 5, 1856.

.To aZZ whom i may concern.'

Be it known that I, JOSEPH M. LIPPIN- GOTT, of Pittsburgh, in the countyof Allegheny and State of Pennsylvania, have invented a new and usefulImprovement in Locks for Banks and Safe-Doors; and I do hereby declarethe following to be a full, clear, and exact description t-hereof,reference being had to the annexed drawings,forming part ofthisspecification, in which- Figure l, is a perspective view of theinterior of my bank lock, with the top of the case removed. Fig. 2, is aperspective representation of the exterior of the same lock. Fig. 3, isa perspective representation of the interior of my lock, with thelocking bolt and wrench pinion removed, so as to exhibit the spring boltand tumbler chamber. Fig. 4L, is a perspective view of the wards andtumblers placed side by side, in the same relative position as theyoccupy when in the tumbler f chamber, but removed therefrom. Fig. 5,exhibits the spring bolt which actuates the tumblers, together with oneof the tumblers, showing their relative position in the lock. Figs. Gand 7 are a side and edge view of the key used to open my lock. Fig. 8,is the wrench used to turn the wrench pinion.

In the several figures like letters of reference refer to similar partsof my lock.

My improvement consists in the use of a stationary'tumbler chamber, andin the use of a slot or aperture in the tumblers into which the groovesfor the passage of the 4fence open, but distinct therefrom, to enablethe tumblers to resume their normal position whenever the key isremoved, when the lock is unlocked as well as when it is locked, toprevent the possibility of taking an impression of the tumblers for t-hepurpose of making a false key.

To enable others skilled in the art to make and use my invention, I willproceed to describe its construction and operation.

In the drawings, a, is the bedplate or case of the lock, Z), the top ofthe case or cover.

UZ is the wrench or handle, by which the bolt 'Z is moved in locking orunlocking when the tumblers are set by the insertion of the key b, intothe keyhole c. The keyhole c, is of the exact width and thickness of theblade, Z), of the key. A tumbler chamber, f, (see Fig. 3) is attached tothe bedplate, a, of the lock midway from either side. It is a small,hollow, rectangular box, open at top and 'with a horizont-al groove g',extending'about of its length, at the proper height to receive the fencela, of the boltl i. The spring boltl Z, resting on the bedplate a, ofthe lock enters an aperture in the base of the tumbler chamber intowhich it ts closely, the spring s, pressing it back into the tumblerwhenever it'V is temporarily displaced by the introduction of the key.The bolt z' (see Fig. 1) has a slot or groove e through it at its rearend, of the widthrof the tumbler chamber 'through which the tumblerchamber projects when the bolt Z, is in place. The uprights lc, 7c,serve to keep the bolt in place. The fence ZL, is a thin strip of ironof the same thickness `as the groove g, in the tumbler chamber, which iswedged on to the face of the locking bolt, at right angles to itslength, and in such position that when the bolt i, is locked, the fencejust enters the groove g', and the-edge of the tumblers, and when thebolt z', is drawn back in unlocking it passes back through the groove.represented as in the position it occupies when the bolt is locked). Thebolt i, has teeth on its lower edge, which gear into the wrench pinionm,vby which it is advanced or drawn back.

In the tumbler chamber f, is placed a series of wards fw, and tumblerst. These are arranged alternately, a ward being placed outside on eitherside. The shape of the wards is seen at Fig. 4, and of the tumblers atFig. 5. All the wards are exactly alike in size and shape. They have ahorizontal groove g, similar in depth and width to the groove in thetumbler chamber, and, when in place, range exactly with it. The bottomof each ward rests on the bottom of theA tumbler chamber; the lower partof the front end of the wards is cut away to admit of the passage of thespring bolt Z, into the tumbler chamber, without touching the wards. Thewards have also a perpendicwA lar groove 0 (see Fig. 4), to admit thekey, of uniform thickness and depth, and about midway from either end ofthe wards.

The tumblers are diii'erently shaped from the wards (see Fig. 5). Theyare nearly square, the lower front corner being` removed to allow thebeveled point of the spring bolt Z, to pass under them to raise and keepthem in place. These tumblers are of the same size and shape, but maydiffer slightly from each other in thickness. Each has a horizontalgroove g, corresponding in width with the groove g, in the tumblerchamber, and grooves g, in the wards; but the depth of the grooves fromthe top of the tumbler diifers in each one, and one only shouldcorrespond in height with the groove in the tumbler chamber f. Thetumblers have not the perpendicular groove o, seen in the wards, as thekey is designed to pass in this groove through the wards, withoutmoving, but at the same time press down the tumblers.

In the middle of each tumbler is a square aperture n, (see Fig. 5,) intowhich the groove g opens. This aperture is of the same size and in likerelative position in each tumbler and is of the same width as the fencek, of the bolt z', but deep enough to allow the play of the t-umblers upand down when the fence is in 'this aperture. There is no such apertureas n in any of the Y wards.

Having described t-he construction of my improved bank lock, I willproceed to describe its operation.

When the key Z9, is placed in the keyhole e, which is situatedimmediately over the perpendicular grooves, 0, in the wards w, theprojections on the bit of the key (see Fig. 6), rest on the edge of thetumblers t. The key is then forced down, the blade passing into theperpendicular groove in the wards, and depressing each tumbler to thedepth of the projection on the bit of the key, which comes in contactwith it. As these projections on the blade, of the key, (see Fig. 6) areall of dierent lengt-h, each tumbler is depressed to a diiferentcorresponding depth in the tumbler chamber (the wards remainingstationary), and the length of these bits on the key bearing such exactrelation to the situation of the horizontal groove in each tumbler, thatwhen the key is pressed down as far as it will go, each horizontalgroove g, in the tumblers, comes eX- actly to the level of the groovesg, in the wards, and the groove g in the tumbler chamber. There is nowno obstacle presented to the entrance of the fence 71 through thepassage formed by the conjunction of all the grooves, g, g, and g, andthe bolt z' may therefore be readily drawn back, in unlocking, by simplyturning the wrench pinion m, by the wrench 0l. So soon,

however, as the bolt z' is shot back, and the fence has reached the endof the groove g, it has fairly entered the aperture n, in the tumblers,which being deeper than the groove g', permits the tumblers to rise, (ifthe pressure of the key is removed) and they are forcibly thrown up bythe react-ion of the spring bolt z', which was forced back by thepressure of the tulnblers when the key was inserted. The tumblers thusall rise to the level of the wards, and the grooves g', in the tumblers,being no longer in range with the groove g, in the wards, the fence 7L,is fastened in its place, and the bolt z', cannot be thrown forwardwithout again using the 'key to adjustthe tumblers as before. It is thusmanifest that it is necessary to arrange the tumblers with the key inlocking as well as unlocking the bolt z', and that as the tumblers arethrown up even at top with the wards, whenever the key is withdrawn,there is no opportunity aorded to take an iInpression of the tumblerswhen set, for the purpose of making a false key.

If it should happen that the key should be lost or mislaid, or for anyreason it should become desirable to change key, it may be done bytaking out the tumblers, and arranging them in different relative orderin the tumbler chamber, when it will require a nev and different key tolock and unlock the bo t 2'.

What I claim as my invention, and desire to secure by Letters Patent,is,

l. The use of a stationary tumbler chamber with movable Wards andtumblers, in combination with the fence L, constructed and arrangedsubstantially as hereinbefore set forth.

2. The use of an aperture n, in the tumblers t, into which the groovesg, for the passage of the fence open, but distinct therefrom, for thepurpose of allowing the tumblers to resume a position in which thegrooves are out of range, while the fence is yet engaged in thetumblers, substantially in the manner and for the purpose hereinbeforeset fort-h.

In testimony whereof, I have hereunto set my hand this first day ofJuly, A. D. 1856.

JOSEPH M. LIPPINCOTT. Witnesses:

I. F. SLAGLE, JOHN A. MARTIN.

